Interventions for Babesia (and Plasmodium)

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1 Interventions for Babesia (and Plasmodium) Susan L. Stramer, Ph.D. May

2 Babesiosis Malaria-like illness caused by Babesia spp. Asymptomatic fatal Non-specific symptoms (malaise, fever, etc.) Hemolytic anemia Onset 1-9 weeks after exposure General mortality 5-9% 21% immunocompromised At risk: infants, elderly, immunocompromised, asplenic, red cell disorders However, risk groups not limited to above Fang and McCullough, 2016, Trans Med Reviews Herwaldt et al., 2011, TTB in the US, Ann Intern Med Meldrum et al., 1992, Babesiosis in NY, Clin Infect Dis 2

3 Babesia microti and Babesia spp. Intraerythrocytic tick-borne parasite Most frequent cause of tick-borne TT-fatalities reported to FDA 162 CDC ( ) + 72 ARC ( ) TTB cases All B. microti except 4 B. duncani TTB underreported/incomplete 9 endemic states 99% B. microti B. divergens B. duncani Incidence of reported cases of babesiosis by county of residence (2011) MO-1

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5 Outside of the US Reports of babesiosis worldwide (>100 babesia sp): Japan, Taiwan, Europe, S Africa, S America, Australia 39 human cases published in Europe; all clinically severe and involved immunocompromised patients: B. divergens (mainly a bovine parasite) B. venatorum (EU1), and B. microti Babesia variants are found in Korea (KO1) and Taiwan (TW1) B. microti-like transfusion transmission in Japan - donor presumably infected in Japan Canada first reported case babesiosis in 1999; however, in 2001, TTB case reported (actually occurred in 1998); 1 B. microti pos donor ID d RBCs 6 mos following donor s travel to Cape Cod, MA (endemic area - US) On f/u, donor remained PCR pos/ab pos (IFA 1:1024) 6

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June 2012-Sept 2014 tested donations from 4 states

Followed donors for Ab/DNA clearance Using our HV

7 June 2012-Sept 2014 tested donations from 4 states (CT, MA, MN, WI) by investigational antibody (AFIA) and DNA (PCR) Determined parasite loads (qpcr) and infectivity (parasitemia in hamsters) Followed donors for Ab/DNA clearance Using our HV system, compared rates of TTB: screened vs unscreened blood 8

8 PCR-Positive Donors DNA Decline 86% resolved reactivity by 1 year 9

9 PCR-Negative Donors Ab Decline 8% resolved reactivity by 1 year 10

10 NEJM Time period (June 2012-Sept 2014) Extended to March # Donations Screened 89, ,473 # Total Pos # DNA Pos # WP Pos # PCR Infectious/total # Infectious/total DNA 1y Ab 1y In high-risk counties, TTB screened blood, TTB unscreened blood TTB cases overall during study period 335 (0.38%) 67 (20%) 9 (1:9900; 13% PCR pos) 25/46 (54.3%) 27/93 (29.0%) 86% 8.0% 0/75,331 14/253,031 OR=8.6; p= ; 10 PCR pos (34.5%) 2-7 mos donor f/u 964 (0.30%) 144 (15%) 16 (1:19,500; 11% PCR pos) 29/54 (53.7%) 31/107 (29.0%) Difference p= % 8.3% 0/312,473 23/1,254,819 OR=11.7; p= ; 20 PCR pos (39.2%) 2-7 mos donor f/u 11

11 Transfusion 2017 early on-line

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13 Babesia Investigational Testing Results Specificity = % PPV = 98.26% Totals Testing Totals 22,174 39,375 31,178 40, ,981 27, ,778 Index Reactive Testing Category IFA and PCR Confirmed IFA only Confirmed Non-confirmed PCR only Confirmed Non-confirmed or NT 16 Total Reactives For 2015 & 2016 numbers, reactives for 13 IFA only are not shown. (11 without additional sample to test and 2 pending testing.) 2/28/

15 Donors Implicated in ARC Recipient Complications Residence of Babesia-Positive Donors (Pins) N=72;

16 64 of 72 (89%) positive donors reside in New England or Mid-Atlantic states State # Positive donors Connecticut 19 Massachusetts 18 Maine 4 Maryland 1 New Hampshire 4 New Jersey 8 New York 6 Pennsylvania 4

17 Donors Distribution by month of the blood donations associated with B. microti transfusion cases (N=72); Month of Donation

Procleix Babesia Assay on the Procleix Panther System Assay in development / Panther not available for commercial use Preliminary Performance Characteristics Sample preparation: method for whole

18 Procleix Babesia Assay on the Procleix Panther System Assay in development / Panther not available for commercial use Preliminary Performance Characteristics Sample preparation: method for whole blood specimens Compatible with target capture/tma, and end-point chemiluminescent or real-time fluorescent detection Compatible with current fully automated system: Procleix Panther System Species detection: detect all species known to cause human disease world-wide B. microti, B. divergens, B. duncani, and B. venatorum Analytical sensitivity: comparable to other TMA blood screening assays 100% detection at 30 copies/ml 95% detection at copies/ml Assay specificity: comparable to current blood screening assays > 99.95% specificity with no cross reactivity to other blood-borne pathogens Testing formats: individual donor samples/qualifying in pools of 4, 8, and 16 donations

Assay Workflow: Procleix Babesia Assay Procleix Panther system

Modified Procleix Xpress System 0.9 ml 0.

19 Assay Workflow: Procleix Babesia Assay Procleix Panther system Individual donor lysates (IDL) or pooled donor lysates (PDL) Modified Procleix Xpress System 0.9 ml 0.3 ml Whole Blood + 3 ml Parasite Transport Medium (PTM) 3.9 ml lysate x ml pooled donor lysate Procleix Panther System Sample traceability by Procleix NAT Manager Deconvolution of reactive PDLs by testing IDLs

20 Overall Babesia RNA Reactivity: ARC Testing Jul 22-Sep Jan 14-Apr Total Lot(s) Formulation A B B (+ new cutoff) A, B Number Tested 5,791 15,619 18,577 39,987 Number Confirmed Positives / Number Reactives (%) 5/21 (24) 10/18 (56) 4/5 (80) % Specificity /45 (42) Positive Frequency 1:1158 1:1562 1:4644 1:2104 States Tested CT, ME, NH, VT CT, ME, NH, VT CT, PA, NJ, DE CT, ME, NH, VT, PA, NJ, DE 22

21 Details of Reactivity of Confirmed Positives # Conf d Positive by Lot # Rx/6 reps tested neat # Rx/6 reps tested 1:16 Ab Status (IFA > 1:64) State of Positive Donors Lot 1 5/5 4/5* 3/5 Lots /10 10/10 9/10 Lots 5-6 4/4 4/4 4/4 *1 discrepant sample Reactivity: neat (4/6), pool of 4 (1/3), pool of 8 (0/3), pool of 16 (0/3), Ab Neg, CT resident 1 to % 5101 to % to % to % CT (4), ME (1) CT (8), NH (1), ME (1) CT (3), NJ (1) VT 2534 PA 5295 NY NH 3763 NJ 4217 DE 20 ME MA RI CT 20,280 23

22 Inactivation of B. microti in RBCs and platelets in 100% plasma Pre-UVA control 24

23 Infectivity of stock aliquots. Blood was collected from highly parasitemic hamsters ( 35% of red cells parasitized) and serially diluted in PBS. The three highest dilutions were injected into naïve hamsters and the development of parasitemia monitored up to five weeks after injection. Percent infected of 24 total hamsters: platelets and red cells 25

24 Pretreatment Control x10^8 parasites/ml 26

25 Inactivation of Babesia microti with Amustaline/GSH in Red Blood Cells 1 Laura Tonnetti, 2 Andrew Laughhunn, 1 Aaron M. Thorp, 1 Irina Vasilyeva,, 2 Kent Dupuis, 2 Adonis Stassinopoulos, 1 Susan Stramer 1 American Red Cross Holland Laboratory, Scientific Affairs, Rockville, MD; 2 Cerus Corporation, Concord, CA Parasitemia was detected in hamsters injected with up to 10-5 dilution of the control samples, while no parasites were detectable in the blood smears of any hamsters receiving neat test samples. Log Titers (ID 50 /ml) a Log Reduction b Replicate Control T=0 Test T=3h Test Postexchange T=24h Test T=3h Test Postexchange T=24h < 1.0 < 1.0 >5.8 > < 1.0 < 1.0 >5.9 > < 1.0 < 1.0 >5.8 > < 1.0 < 1.0 >6.2 >6.2 Mean ± SD 5.0 ±0.2 < 1.0 < 1.0 >5.9 ± 0.2 >5.9 ± 0.2 a. 1.5 ml injected/hamster; 1.5 ml 6 hamsters or 9 ml total inoculum/replicate). b. Log reduction is calculated as Log (Control T=0 titer Test titer). 27

Plasmodium spp. Agents of human malaria P. falciparum, P. vivax, P.

knowlesi Found inside red and liver cells Transmitted by female

26 Plasmodium spp. Agents of human malaria P. falciparum, P. vivax, P. malariae, P. ovale & P. knowlesi Found inside red and liver cells Transmitted by female anopholene mosquitoes Usually found in tropical or subtropical areas >200 million cases/year 665,000 to 1.24 million deaths/year > 80% occur in sub-saharan Africa 90% is P. falciparum Periods of fever & chills Blood banks challenges differ by country blood safety vs. availability 28

27 Transfusion-Transmitted Malaria (TTM) in the US 93 cases * WB:63% RBCs:31% Platelets:6% Since: TTM is rare Only 7 cases since 2002 > 2/3 rd s of cases attributed to donors with a previous history of malaria (i.e., semi-immune) associated with residence in an endemic country military service in Vietnam *Mungai et al., NEJM 2001;344:

28 Imported malaria cases by country and TTM TTM: 11 all from West Africa, 10 P. falciparum (1 P. malariae) 10 emigrated, 5 had or had been treated for malaria O Brien et al TMR 29:

29 111 patients rec d treated WB; 112 rec d untreated WB 65 patients exposed to parasitemic blood... 8/37 untreated 1/28 treated 22 vs 4%; p = Closed circles show TTM cases relative to donor parasite loads when allelic discrimination was used in the definition of TTM

30 Summary Prospective blood donation screening for B. microti is feasible and has removed ~1000 potentially infectious units of blood including 15-20% PCR positive => infectious 1:10,000-1:20,000 window-period units => infectious Ab positivity persists for years => donations from such donors unlikely to be infectious in absence of RNA/DNA Other technologies in development Highly sensitive RNA NAT methods (vs DNA PCR) Would a highly sensitive NAT method be adequate in the absence of Ab testing? Eliminates likely all infectious donations (and avoids deferral of high numbers of antibody pos donors with resolved infections) RBC Pathogen Inactivation is highly effective in preventing both TTB and TTM 33

Reducing Babesia and Malaria Risks: Testing, Donor Selection, Inactivation. Susan L. Stramer PhD IPFA 23 rd Meeting May

Reducing Babesia and Malaria Risks: Testing, Donor Selection, Inactivation Susan L. Stramer PhD IPFA 23 rd Meeting May 26 2016 Babesiosis Malaria-like illness caused by babesia spp. Asymptomatic fatal